First, the mysterious killing at the university of michigan medical school. When an aspiring surgeon was found dead by a single shot. But there's no clues as to what went so terribly wrong. Alex perez is tracking the case. Reporter: Good morning, george. The police have no weapon and none of his valuables were missing. A co-worker found him after he failed to show up to work. Charming, with an infectious smile and no known enemies. The mysterious murder of paul DeWOLFE HAS A COMMUNITY ON-EDGE This morning, as a killer is on the loose. We never heard anything like a gunshot or anything. Reporter: Dewolfe, who was an active duty second lieutenant in the air force, was found wednesday in his bedroom, inned the offcampus fraternity house he shared with other medical students. Killed by a single gunshot wound. Police are treating the case as a homicide. No suspects have been named. No weapon found on the scene. And nothing missing or out of place in his room. In western michigan, where DeWOLFE GREW UP, HIS LOVED ONES Are in disbelief. He's like, I'm going to cure cancer one day. He had such great aspirations for life. And if you knew paul, he would have done it. He's the type of person that would have cured cancer. Reporter: Dewolfe posted on facebook about his friends, his love of scuba diving and running marathons. His friends say, he loved life. He loved everyone, regardless. He taught me to be a better, more caring person. And I love him for it. Reporter: Dewolfe was laser-focused on his surgical training. Part of a research team that was working on a treatment for acl tears. In a statement, one fellow RESEARCHER SAID, DeWOLFE WAS THE Epitome of everything great in the field of medicine. The university of michigan has increasing police patrols and warning students to stay alert, as investigators now hunt for his killer. AND FAMILY MEMBERS laid DeWolfe to rest monday evening. He was set to graduate from medical school next year.

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